A microprocessor can be taken up as an example of a data processor. For a state-of-the-art microprocessor and a system including it, functions required of an application running in the system become more highly functional and complicated along with miniaturization of LSI (Large Scale Integration). In developing highly functional applications, from a perspective of an efficient way of development, it is usual to exploit existing applications and combine them to develop a more highly functional application. In this regard, an existing application is designed to run in a conventional system configured with a conventional microprocessor and such application is inseparable from the configuration of the conventional system. Changing the system configuration takes a considerable amount of man-hours for development, though this amount is less than man-hours that would be taken to develop an existing application again. Therefore, in most cases, existing application programs must be run in their associated conventional systems. In order to combine and run existing applications designed to run in different existing systems, the existing systems need to be combined so that they will cooperate.
The above-mentioned “conventional system” refers to a system configured with a single central processing unit and a single operating system (OS). The above phrase “the existing systems are combined so that they will cooperate” means that, particularly, a number of diverse operating systems are combined so that they will cooperate in parallel.
Patent document 1 describes a technique for combining a plurality of operating systems for conventional systems so that the operating systems will cooperate, while maintaining the reliability and security of each of the conventional systems.
[Prior Art Document]
[Patent Document]
    [Patent Document 1] Japanese Laid-Open Patent Application No. 2008-097173